1. Technical Field
The present invention pertains to an improved jewelry ring assembly of the type having two annular rings, one movably retained by the other, and to the method of manufacturing such assembly. Although the preferred embodiment described herein is a finger ring, it will be understood that the principles of the invention apply equally to rings worn on other parts of the body or suspended from chains, pins and the like.
2. Discussion of the Prior Art
It is known in the prior art to manufacture finger ring assemblies made of two rings, namely a base or inner ring that fits on the wearer's finger, and a retained or outer ring that is engaged by the base ring. Example of such ring assemblies are found in U.S. Pat. Nos. 1,431,652 (Grossman), U.S. Pat. No. 1,586,606 (Cain), U.S Pat. No. 5,161,392 (Wiriath et al.), U.S. Pat. No. 5,228,316 (Meyrowitz), U.S. Pat. No. 5,678,428 (Pasquetti) and Australian Patent No. 208883 (Preston). The ring assemblies disclosed in the Cain, Wiriath et al., Meyrowitz and Pasquetti patents are made from at least three parts which are assembled in various manners. In order to place and then retain the outer ring on the outside surface of the base ring, the base ring is provided in two pieces that are joined together after the outer ring is in place. The need for a two-piece base ring arises from the fact that annular edges of greater outside diameter than the inside diameter of the retained ring are required in order to hold the retained ring on the base ring. This required size relationship, however, prevents placement of the outer ring onto the base ring unless the base ring is initially disassembled.
The Grossman and Preston patents disclose respective ring assemblies wherein the base ring is made of a single piece. The outer surface of the base ring has an annular channel disposed between two raised annular edges of greater diameter. The base ring is initially sized such that the outside diameter of the annular edges is slightly smaller than the inside diameter of the retained ring, thereby permitting the retained ring to be moved axially over one of the edges of the base ring and into alignment with the base ring channel. The base ring is then radially expanded whereby both its channel and its retaining edges experience a diametric increase until the aligned retained ring is disposed within the base ring channel between the annular retaining edges. The expansion ultimately causes the retained ring to fit tightly as an inset in the base ring channel, the tight fit preventing relative movement of the two rings in the final assembly.
It is aesthetically desirable to provide a jewelry ring assembly of the type described wherein the retained ring is both freely rotatable about the base ring and capable of freely wobbling (i.e., axially skewing) between the outer retaining edges of the base ring channel. It is also aesthetically desirable that the retaining edges of the base ring be formed as a smooth transition from the base ring channel rather than providing a sharp step or right angle transition between the channel and retaining edges. It is further desirable that the base ring be made of a single piece rather than two parts that must be assembled after the retained ring is in place. None of the ring assemblies described above meet all of these criteria.